1. Field of the Technology
The present technology relates to a post-processing apparatus that performs post-processing on recording sheets.
2. Description of the Related Art
The development of post-processing apparatuses that perform post-processing on recording sheets subjected to processing such as image formation has been underway in recent years. Such a post-processing apparatus has post-processing functions such as stapling, punching and bookbinding functions.
Post-processed recording sheets are loaded into a tray provided downstream of the post-processing apparatus. However, there is a problem in that depending on input conditions (the number of sheets bound, the number of staples, stapling positions, the number of sheets ejected or the like), a desired number of post-processed recording sheets cannot be loaded onto the tray, which may case any excessive recording sheets to fall off the tray.
Japanese Patent Laid-Open No. 06-008666, Japanese Patent Laid-Open No. 03-063192 and Japanese Patent Laid-Open No. 2007-197188 disclose post-processing apparatuses which can prevent post-processed recording sheets from falling off a tray.
The invention disclosed in Japanese Patent Laid-Open No. 06-008666 can change a stapling position for each ejected bundle of recording sheets, thereby avoid overlaps in the stapling position among bundles and reduce the bulk of the bundles.
The invention disclosed in Japanese Patent Laid-Open No. 03-063192 is configured such that when the number of recording sheets in a bundle exceeds an upper limit of stapling processing, the recording sheets can be stapled within the upper limit with the remaining recording sheets left non-stapled.
The invention disclosed in Japanese Patent Laid-Open No. 2007-197188 is configured such that when an upper limit of stapling processing is exceeded, stapling processing can be cancelled.
However, the invention disclosed in Japanese Patent Laid-Open No. 06-008666 changes a stapling position for each bundle of recording sheets automatically, to prevent the bundles of recording sheets from falling off the tray. This causes a problem in that the bundles are not stapled at positions desired by a user.
With the inventions disclosed in Japanese Patent Laid-Open No. 03-063192 and Japanese Patent Laid-Open No. 2007-197188, when the upper limit of stapling processing is exceeded, stapling processing of the remaining recording sheets is cancelled automatically. This causes a problem in that processing is not performed as the user wishes.
On the other hand, the user has a desire to handle recording sheets set to be stapled and recording sheets not set to be stapled in a single job, i.e., in a single processing run. The inventions disclosed in Japanese Patent Laid-Open No. 06-008666, Japanese Patent Laid-Open No. 03-063192 and Japanese Patent Laid-Open No. 2007-197188 cannot satisfy such a desire.
It is an object of the present technology to provide a post-processing apparatus that can handle recording sheets set to be stapled and recording sheets not set to be stapled in a single job and reliably prevent post-processed recording sheets from falling off a tray.